Chloride-Liberal vs Chloride-Restrictive Fluid Strategies in the ICU

Greg Martin, MD


April 02, 2013


Concern about chloride has existed for many years and has become particularly of interest as we have discerned more of its effects on renal physiology and clinical outcomes. Recently, studies have shown that chloride-rich fluids are associated with a prolonged time to first micturition and a decrease in urine output after major surgery.[2,3] In addition, a double-blind, randomized, controlled trial demonstrated that 2 L of normal saline given to normal human volunteers decreased renal cortical perfusion compared with a more balanced solution.[4]

Because this study was conducted in a time-series intervention, it is impossible to know with confidence that chloride was the cause of the adverse consequences seen during the period in which chloride-rich fluids were used. It is certainly possible that other simultaneous changes in patients or management strategies could have contributed. However, the consistency and concordance of the data raise the likelihood of a real cause-effect relationship. If so, it would suggest at least a need to overhaul the way we use intravenous fluids to treat critically ill patients and possibly a need to return to the laboratory to develop more appropriate intravenous solutions.

At the very least, this study reinforces that fluids, despite being prescribed almost daily in every hospitalized patient and generally ignored for their potential to cause problems, require much more thoughtful consideration about what, how, when, and how much they should be used in critically ill patients.